Impact-tool.



1%. 739,440. PATENTED'SEBT. 22,1903, s. OLDHAM.

IMPACT TOOL.

APPLICATION FILED OUT. 21, 1902.

- and usefullmprovements in Impact-Tools, of

Fatented September 22, 190%.

pea-1D; STATES? *PAI NC W O g 1 M PACT-TOOL.

SPECIFICATION forming part of Letters Patent No. 739,440, dated September 22, 1903.

Application file d October 21,1902. Serial No. 123,108. (No model.)

To aZZ whom. it may concern:

Be it known that LSAMUEL OLDHAM, a cia- 1 zen of the United States, residing at Frankford, in the county of Philadelphia and State of Pennsylvania, have invented certain new which the following is a specification.

My invention has relation to that class of impact-tools in which a piston or hammer reciprocates in a'cylinder and delivers on its downstroke a blow upon a tool; and in such connection it relates to the construction and arrangement of such-a tool. I

The principal object of my inventionis to provide in a pneumatic .tool or. hammer, in

conjunction with a 'reciproca'tory piston, a tool-shank arranged in the path of andadapted to be struck by the piston upon its'downstroke, a ratchet secured to the tool-shank, a means for turning the ratchet, and a mechanism controlled by the piston on its upstroke and arranged to operate said means.

The nature and scope of my invention will be more fully understood fromthe following description, taken in connection with the accompanying drawings, forming part hereof, in which- Figure 1 is a side elevational view, partly in section, of an impact-tool embodying main features of my invention. Fig. 2 is an en'- larged longitudinal sectional view of the main body of the tool. Figs. 3 and 4: arecross-sec tional views taken, respectively, on the lines 3 3 and 4t 4 of Fig. 2. Fig. 5 is a planview of the cam-groove in the sleeve'surrounding the piston or hammer. Fig. 6 is a longitudinal view of a modified form of'mechanism for turning the tool-shank. Figs. 7, 8, and?) are cross-sectional views taken, respectively,

onthelines 7 7, 8 8, and 9 9 of Fig. 6. Fig. 10 is a View similar to Fig. 6, but illustrating a still further modified form of tool-turning mechanism. Figs. 11,12, and 13 are cross-sectional views taken, respectively, on the lines 11 11,

12 12,- and 13 1.3 ofFig. 10; and Fig. l tisaperspective view, partly sectioned, of the throttle or cut-oft valve for the tool.

Referring to Figs. 1 to 5 of the drawings, a represents the external casing ofthe tool, to one end of which is secured the operatinghandle b. In the other. end of this casing a is arranged the socket a, adapted to receive longitudinal slots 6 of I the cylinder e.

' the shank cl of a tool d. Within the casing a is arranged the cylinder 8,111 which recipro- Ycates apiston or hammer f. Between the easing a and cylinder 6 is provided a sleeve 9,- arranged to oscillate'around said cylinder e. The" lower end of the sleeve 9 has its periphery cut out to receive a pawl r, as clearly illustrated in Fig. 3. This pawl g is pivoted, as at g in the sleeve 9 and has a movement inward of the sleeve 9 under the influence of the spring 9 The pawl g is adapted to en gage the teeth of a'ratchet-wheel 9 arranged within the sleeve g. This ratchet g has a po lygonal-shap'ed opening for the reception of a correspondingly-shaped extension or head 61 removed therefrom; When inserted in said ratchet g it is evident that the tool will turn with said ratchet. Motion is conveyed to the sleeve g, and consequently to the pawl g, as follows: The piston or hammer f is provided with a transverse pin or shaft f, working in pin or shaft f projects beyond the cylinder e'and enters cam-slots g in the sleeve g, as illustrated in Figs. 2 and 5. The pin or shaft f by preference projects diametrically through the piston f and each end traverses successively a straight slot 6 of the cylinder 6 and a cam-slot g of the sleeve g. In this instance the slots e in the cylinder e and cam-slots g in the sleeve 9 are diametrically arranged in respectively the cylinder and sleeve.

The

From this description it will be understood thatthe piston or hammer f reciprocates in a straight line in the cylinder 6 Without turnring therein and in its reciprocation the pin or shaftf' oscillates the sleeve 9 first in one direction and then in an opposite direction, the slots g being arranged so that aprede- ,termined throw of the sleeve results from 'a movement up or down of the pin f; The oscillation of the sleeve g, say, from right to left, as illustrated in 3, causes the pawl to bear against the teeth of the ratchet g and to turn said ratchet and'the tool d a pre-..

determined distance. The oscillation of the sleeve gin an opposite direction causes the pawl g to slide loosely on the teeth of the too ratchet g, and no movement of said ratchet or of the tool d takes place. It is. desirable that the movement of the ratchet and tool should take place before the tool-shank (Z is struck by the hammer or piston f, and hence the slots g are so arranged that the sleeve g oscillates to the left to turn through the pawl the ratchet 9 upon the upstroke of the piston or hammer.

From the above description it will be readily understood that the to-and-fro or reciprocatory movement of the piston is transformed and transmitted by an oscillatory movement of the sleeve ginto a step-by-step rotation of the ratchet g", and consequently of the tool (1. This rotation of the tool is of importance and desirable, for instance, in drilling holes in blocks of stone or metal, and, so far as I am aware, in this class of tools, in which the shank of the tool is separated from the piston and receives from time to time blows therefrom, said shaft has not been turned automatically by the movement of the piston or hammer. i

In Figs. (5 to 9 an equivalent but modified form of mechanism for turning the ratchet g and tool (1 is illustrated. In this instance instead of a sleeve an oscillating lever g is used. This lever g carries the pawl g, which operates the ratchet g and is pivoted intermediate of its ends, as at g, in the cylinder 6. The inner end of the lever g is provided with a stud or button g traveling in a camslot g formed in the lowerend of the piston f. A pin 9 projecting inward from the cylinder e, enters a straight slot also formed in the lower end of the piston f and serves to prevent the piston turning during its reciprocation in the cylinder 6.

In Figs. 10 to 13 the construction is similar to that illustrated in Figs. 6 to 9 but in this instance the inner end of the lever g rests in a straight slot 9 the base of which is inclined. A spring g, bearing 011 the inner end of the lever g presses said inner end down upon the inclined floor or base of the slot 9 In the handle I) of the tool is arranged a throttle or cut-off valve of improved construction. As preferably constructed it consists of a plug 1), arranged to slide up and down in a tube W. The tube 19 has two openings b diametrically arranged and connecting the live-fluid inlet 1)" with the inlet 1) in the handle of the tool.

The plug 1) also has a duct 1) traversing it and adapted to register with the openings 0 of the tube 12 when depressed against the action of a spring D The plug 1) has a squared shank b around which is coiled the spring 6 this spring normally tending to withdraw the shank b and plug b from the tube. A trigger b is arranged to bear on the shank b and when depressed to force said shank b and plug b inward in the tube to cause the duct or opening I) of the plug to register with the opening 12 in the sleeve 12 On the squared shank b is placed a collar D having a series of holes Z2 arranged to receive successively a pin b, projecting from the top or rim of the tube b The collar 19 when turned will turn the plug 1) and cause the duct b to register more or less with the openings 11 of the tube. When the required adjustment of the duct b is obtained by the turning of the collar h the collar is locked to the tube b by causing the pin Z) to enter the appropriate hole 7) Having thus described the nature and objects of my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an impact-tool, areciproeating piston, a cylinder wherein said piston is adapted to move, a tool-shank arranged in the path of and adapted to be struck by the piston upon its downstroke, a ratchet secured to the toolshank, a pawl arranged to turn said ratchet in one direction and a mechanism located outside the cylinder and controlled by the piston in its upstroke, said mechanism arranged to operate the pawl and thereby turn the ratchet and tool-shank.

2. In an impact-tool, a tool-shank, aratchet to whichthe tool-shank is secured, a pawl arranged to operate said ratchet to thereby turn the toolshank, a cylinder, a piston recipro eating in said cylinder and arranged to strike the tool-shank on its downstroke, a sleeve located outside said cylinder and having a cam-groove, said sleeve arranged to turn on said cylinder, and a pin carried by said piston and arranged to enter the cam-groove of the sleeve, said pin traversing a straight groove in said cylinder.

In testimony whereof I have hereunto set my signature in the presence of two subscribing witnesses.

SAMUEL OLDHAM. lVitnesses:

J. WALTER DoUeLAss, THOMAS M. SMITH. 

